Eddy Current Probe (ECP) sensor systems have been used since the 1970's for non-contact displacement measurements, in the monitoring and protection of rotating machines operating with journal (sleeve) bearings. ECP systems are also commonly known as “Proximity Probe Systems”.
In many businesses/industries, such as the oil & gas business, a machine is designated a ‘hazardous area’ with respect to flammable gases—divided into different ‘zones’ of ignition or similar. There are many requirements to be fulfilled to enable placement of sensors and electronics in a hazardous area. Conventionally only the sensor, such as an eddy current probe sensor and an appropriate oscillator or even driver is placed on and in close proximity to a rotating machine to be monitored. Individual cabling from each sensor has then been laid to a safe area, usually a control room, where vibration and condition monitoring systems have resided. This could be seen as inflexible. There thus seems to be room for improvements.